Managing floating IP addresses

A virtual machine connected to a virtual network can be accessed from public networks, such as the Internet, by means of a floating IP address. Such an address is picked from a physical network and mapped to the VM’s private IP address. The floating and private IP addresses are used at the same time on the VM’s network interface. The private IP address is used to communicate with other VMs on the virtual network. The floating IP address is used to access the VM from public networks. The VM guest operating system is unaware of the assigned floating IP address.

Prerequisites

  • You have a virtual router created, as described in Creating virtual routers.
  • The virtual machine to assign a floating IP to has a fixed private IP address.
  • The virtual router connects the physical network, from which a floating IP will be picked, with the VM’s virtual network.

To create a floating IP address and assign it to a virtual machine

  1. On the Compute > Network > Floating IPs tab, click Add floating IP.
  2. In the Add floating IP address, select a physical network, from which a floating IP will be picked, and a VM network interface with a fixed private IP address.

  3. Click Add.

To re-assign a floating IP address to another virtual machine

  1. Click the ellipsis icon next to the floating IP address, and then click Unassign.
  2. Once the VM name disappears in the Assigned to column, click the ellipsis icon again, and then select Assign.
  3. In the Assign floating IP address window, select a VM network interface with a fixed private IP address.
  4. Click Assign.

To remove a floating IP address

  1. Unassign it from a virtual machine. Click the ellipsis icon next to the floating IP address, and then click Unassign.
  2. Click the ellipsis icon again, and then select Delete.